Plate Rolling / Roll bending Roller worn

[gerdogan]

Hello all,

I wonder if anyone has experience coating plate rolling machines' rollers. A company uses a plate roller to form a cylindrical shape of aluminium sheets, and as the roller has some scratch marks due to wear over time, those scratch marks leave unwanted stains on the aluminium sheets. What would you suggest to me? I thought applying 2 mm metcoloy 2 coating those rollers would be enough. As the machine is the core element of their production line company hesitated to apply a coating and consider using it the way it is.

I do not have any info about the machine yet but to my best knowledge, the roller material is 1050 steel with a 500mm diameter.

Thank you all in advance

[Vadim Verlotski]

Hi Gerdogan,
To avoid scratches on the rolls, the hardness of the steel surface must be as high as possible. Metcoloy 2 only has a hardness of 48 HRC, which is not much. For example, conventional hard chrome plating gives more than 68 HRC, and applying galvanized hard chrome, 20-50 microns thick, to steel is much easier and cheaper than applying 2 mm Metcoloy 2.
If you want to use thermal spraying, tungsten carbide (WCo, WCoCr) coatings applied by HVOF and HVAF methods give good results in terms of hardness (over 70 HRC). Usually about 200 µm of such a coating is sufficient.